Celiac Disease

Question: How do I identify and treat celiac disease in my diabetic patients?

Answer: Celiac disease is an autoimmune disease affecting the small bowel that occurs in genetically predisposed patients. An inappropriate T-cell–immune-mediated response to storage proteins found in wheat, rye, and barley (collectively referred to as gluten) results in a loss of absorptive villi and hyperplasia of the enteric crypts in the small bowel.

Celiac disease once was considered rare; however, recent studies show the prevalence to be approximately 0.5–1% in the U.S.

Clinical manifestations of celiac disease are highly variable, involving multiple organ systems. Celiac disease can occur at any age, with a peak diagnosis between the fourth and sixth decades. Studies show that symptoms precede diagnosis by 11 years on average.¹

Celiac disease is categorized into three forms based on the presence or absence of symptoms:

1. Classic-form celiac disease includes symptoms such as chronic diarrhea, abdominal pain, weight loss, growth failure, vomiting, bloating, flatulence, various vitamin and mineral deficiencies, irritability, and constipation. The presence of obesity does not rule out celiac disease.

2. Atypical-form celiac disease includes a wide spectrum of presentations, sometimes with little or no gastrointestinal symptoms, and may now be the most common form. It is characterized by multiple organ system involvement, such as dermatological, liver disease, osteoporosis, hematological, reduced fertility and problems in pregnancy, and cancer and lymphoma.²

3. Asymptomatic (silent)-form celiac disease typically is diagnosed by screening of high-risk patients or by endoscopy or biopsy for some other reason. These patients have positive serological tests and villous atrophy on biopsy.

Diagnosis of celiac disease includes serological tests and biopsy. Patients must be consuming gluten while undergoing these tests. The most sensitive serological tests are IgA anti-human tissue transglutaminase and IgA endomysial antibody immunofluorescense. Positive tests should be followed by multiple biopsies of the proximal small bowel. Diagnosis is confirmed when symptoms resolve with a gluten-free (GF) diet.³

Treatment of celiac disease is a strict GF diet for life.⁴ Because GF foods may be lower in B vitamins (including folate), iron, and fiber, patients must carefully plan to ensure an adequate intake of these nutrients.^5,6 Also, the carbohydrate content of many GF grains and products differs from gluten-containing grains. For these reasons, referring patients to a registered dietitian with expertise in medical nutrition therapy for celiac disease is essential.³

Monitoring blood glucose and insulin requirements closely after starting a gluten-free diet is important in order to make appropriate changes in the insulin regimen.

Failure to maintain the GF diet increases risk for malabsorption of many nutrients, especially iron, zinc, B12, folate, calcium, magnesium, and fat-soluble vitamins; therefore, monitoring these is paramount, and a daily multivitamin may be recommended.² Health care providers should be aware that oats have been found to be cross-contaminated with gluten-containing grains, and consumption by patients with celiac disease is not recommended in the U.S.⁷

Providers should educate patients with celiac disease about the disease and encourage them to join local and national support groups. Finally, continuous long-term follow-up by a multidisciplinary team is a key component in successfully managing these patients.⁵ ▪